Room Measurement Tutorial for Dummies Part 2

[OCA]

Hi, I’m considering grabbing a UMIK1 but my receiver is another room in an equipment rack. Cable would probably need to be 50ft or longer. Any suggestions for setup in this scenario? I figure trying to use a really long hdmi cable is better than trying to use a long mic cable.

Amazon.com

 

[nathan]

trying to use a long mic cable

Keep in mind the UMIK1 does not use a mic cable at all. It uses USB. I would try running USB over Cat cable: USB Extender Over RJ45 Cat 6/5/5e Adapter, RJ45 Ethernet Splitter to USB Extension UP to 50m/164ft, Compatible with Computers, Mobile Phones, Mice, Keyboards, U Disks, Printers, Cameras since that is lower bandwidth than HDMI but: the good news is that you can use the absolutely cheapest extended HDMI solution too, I would guess, since all you are doing it sending audio and enough video to make the connection work.

 

[stonith]

until-

You should be able to get out to long lengths using a powered USB hub in the middle, or an active cable.
How long do you really need?
Active USB cables can go out to 90'


I've no idea how you figure to go from USB to HDMI and back again?

Forgot about active usb hubs. Thanks! The hdmi comment was regarding audio out to the receiver for the test tones.

 

[192kbps]

If Part 4 exists, why can't Part 3 come as soon as possible?

 

[Mick Seymour]

If Part 4 exists, why can't Part 3 come as soon as possible?

Does anyone have a link to part 4.

 

[192kbps]

Does anyone have a link to part 4.

We can wait for part four when we see part three.

 

[Mick Seymour]

I was responding to your post, @192kbps; if part 4 exists...

I thought I may have missed something.

 

[bdvan]

Looks like Amir is busy, can someone with good REW experience post a pseudo-part 3 of this article.

 

[DHzHolden]

Room Measurement Tutorial for Dummies Part 2: Selecting a Measurement Microphone

...In the next tutorial we will get into the meat of these of lessons which is to actually perform the measurements and understand what they mean.

Hi! I loved Part 1, made Room Measurement with REW comprehensible for me. Part 2 ends on the cliffhanger above. where do I go from here? Seems that Part 3 never appeared, or maybe has a different title?

In any event, very helpful, thanks.

Dick

 

[Sal1950]

Hi! I loved Part 1, made Room Measurement with REW comprehensible for me. Part 2 ends on the cliffhanger above. where do I go from here? Seems that Part 3 never appeared, or maybe has a different title?

In any event, very helpful, thanks.

Dick

Hi Dick, welcome to ASR !
Wish I had some easier answers for you here. The original 2 chapters were written by Amir some years back and since he has
started this website I don't believe he has the time available any more to work on it.
Normally I would first refer you to the REW website but currently it doesn't seem to be online. I do hope it is a short term issue and will be back up shortly.

REW room acoustics and audio device measurement and analysis software

REW is free software for room acoustic measurement, loudspeaker measurement and audio device measurement and analysis

www.roomeqwizard.com

There is a very large community of user over at AVS forums with many experienced users willing to answer questions and help.

https://www.avsforum.com/threads/simplified-rew-setup-and-use-usb-mic-hdmi-connection-including-measurement-techniques-and-how-to-interpret-graphs.1449924/

Sorry I don't have a more direct answer for you beyond this.
Sal1950

 

[Robocop]

I concur with Sal. There is no one source to get the perfect starter guide. It takes quite some effort/time to master. REW site is the first go to. You tube has some clips but all are not the complete story but worth watching. I personally found the Dutch and Dutch 8c method useful even though its integrated with REW https://dutchdutch.com/pages/rew-roommatching-guide. I adapted this to mine. Most info is on this ASR web site but takes some trawling to find. Its trial and error and eventually you should get to a satisfactory point. I do run a minidsp flex so have some support from them. It is worth it in the end and an interesting journey.

Robert

 

[levimax]

Especially when starting out I have found it much easier and faster to use the MMM method. I have compared MMM results to multiple averaged measurements and I always get the same result. There are limitations to the analysis you can do but for in room FR measurements for room EQ it works well.

 

[RayDunzl]

Seems that Part 3 never appeared, or maybe has a different title?

Part Three is the "Do It Yourself" part.

 

[DHzHolden]

Especially when starting out I have found it much easier and faster to use the MMM method. I have compared MMM results to multiple averaged measurements and I always get the same result. There are limitations to the analysis you can do but for in room FR measurements for room EQ it works well.

Levi,

Thanks for linking this video, it was an eyeopener, not just for the moving-mic technique, but for further information about REW.

Dick

 

[brass]

My promise to you in return is to give you the world's simplest and most foolproof way to perform room measurements. And do so in a manner that get gets you professional results with substantial ability to go as deep as you want.

...I guess it wasn't so simple...?!

 

[levimax]

...I guess it wasn't so simple...?!

Trying to get useful measurements of a speaker in a room beyond nearfield is one of the hardest and most confusing things I have tried to learn about. I am currently working on putting together an "outside" measurement set up which I am sure will prove to be an adventure as well. Luckily just a hobby so all good fun.

 

[Sal1950]

...I guess it wasn't so simple...?!

Sometimes time and life get in the way. The big Official REW forum is at.

Official REW (Room EQ Wizard) Support Forum

Guides / Links / Notes / Setup / Connection / Testing Official Support Forum for Room EQ Wizard (REW) by John Mulcahy

www.avnirvana.com

 

[GoDawgs]

Oh man, I'm busted again...

Mine's on a short heavy HAM desk stand, on the top of the couch, with velcro markers on the couch and a velcro 'limiter", as it leans forward (to be at ear position).

View attachment 5837

It lets me remove and replace it with really good positional repeatability, with that last horizontal quarter-inch found via the pink noise response at 20khz.

You get a unique by serial number on-axis calibration, and a 90 degree file.

They found the delta from 0 to 90 degrees was very regular, and might use a 90 degree file calculated from the individual 0 degree file.

https://www.minidsp.com/forum/umik-questions/10088-translate-0-degree-calibration-to-90-degree

I only use the on-axis, as I am to retarded to go multichannel (>2) here.

If the pictured microphone set-up should be replaced by a tripod mike stand, wouldn't moving the sofa to place the mike stand in the listener position impact the measured room acoustics? If one has a counter that is approximately 3 inches from the rear of a sofa at the same level (great room with kitchen), could a mini tripod be placed on the counter and then position the microphone to occupy ones listening space? Like moving the stand in the picture to a counter at sofa height immediately behind it. I'm preparing to perform an evaluation of my listening space and I want to get the measurements right. Should I move my furniture or just get the microphone in the premium listening position with nothing moved out of place?

 

[RayDunzl]

f the pictured microphone set-up should be replaced by a tripod mike stand, wouldn't moving the sofa to place the mike stand in the listener position impact the measured room acoustics? If one has a counter that is approximately 3 inches from the rear of a sofa at the same level (great room with kitchen), could a mini tripod be placed on the counter and then position the microphone to occupy ones listening space? Like moving the stand in the picture to a counter at sofa height immediately behind it. I'm preparing to perform an evaluation of my listening space and I want to get the measurements right. Should I move my furniture or just get the microphone in the premium listening position with nothing moved out of place?

I would used a tripod stand to put the mic in the same position as pictured above.

That puts the mic about at the center of where my head would be were I sitting there.

The only thing missing is me.

The technical reason for that is that I figure it is "Good Enough".

Were I at your place, I'm pretty sure I would find a "Good Enough" spot without creating a lot of work for myself.

PS: That couch is extraordinarily heavy, so it doesn't get moved, having been constructed sometime in the prior century and containing a fold-out bed that never gets used.

 

[GoDawgs]

I would used a tripod stand to put the mic in the same position as pictured above.

That puts the mic about at the center of where my head would be were I sitting there.

The only thing missing is me.

The technical reason for that is that I figure it is "Good Enough".

Were I at your place, I'm pretty sure I would find a "Good Enough" spot without creating a lot of work for myself.

PS: That couch is extraordinarily heavy, so it doesn't get moved, having been constructed sometime in the prior century and containing a fold-out bed that never gets used.

Thanks for responding to such an old thread. I'm still waiting for an empty house to perform some room measurements. I'll tripod it to locate it in the same position without using the couch.

The funny thing was when I saw your picture, my microphone was sitting exactly like yours was on my couch. When I saw the word, "busted" in your post beside the photo, I was wondering for a moment if my laptop had 'inadvertently' shared my microphone picture with the forum.

I'll probably get everyone out of the house sometime today so I can run REW and get some measurements.

Thanks again, you have had some really humorous posts on this forum, thanks for that too!